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Clinton's first day on the job

From NBC's Domenico MontanaroNewly minted Secretary of State Hillary Clinton received a boisterous and enthusiastic welcome at the State Department for her first day on the job.

She spoke of the hard work going forward, but praised the career diplomats as the best there are.

"This is not going to be easy. ... It's going to be hard," Clinton told the State Department staff packed into the building. "But if it weren't hard, somebody else could do it, besides the professionals of the Foreign Service and the Civil Service and our Diplomatic and Development Corps."

She also spoke of her own hopefulness for renewed, robust diplomacy in the Obama administration.

"There are three legs to the stool of American foreign policy: defense, diplomacy, and development," Clinton said. "And we are responsible for two of the three legs. And we will make clear, as we go forward, that diplomacy and development are essential tools in achieving the long-term objectives of the United States. And I will do all that I can, working with you, to make it abundantly clear that robust diplomacy and effective development are the best long-term tools for securing America's future."

President Obama and Vice President Biden are slated to pay a visit to Foggy Bottom later this afternoon.